In the mixing and aeration of large bodies of liquid, several different types of mixers have been used, such as floats and pumps. Generally, the flotation types have heretofore been insufficiently controllable in most directions of flow for efficient mixing. Further, most aeration apparatuses used in combination with mixers require various compressors supplying a source of air to the mixer wherein the compressed air is injected into the liquid medium through nozzles and the like. The compressors generally expend great amounts of energy and increase the total cost of operation of the system.
In other applications, pumps and the like have been used, but these often do not provide sufficient rates of flow for the efficient mixing required in the equalization basins, as well as oxidation ditches, sludge holding tanks and other special applications. Mixers are also used in aerated lagoons in which biological solids are in equilibrium within applied waste. The basin is of sufficient depth, normally six to twelve feet and oxygen is furnished by mechanical aeration to create a turbulence level sufficient to provide adequate liquid mixing. As a result of the mixing, uniform distribution of the waste and dispersion of the oxygen is achieved to promote efficient waste biodegration. Moreover, previous mixing and air injecting appratuses have tended to be overly expensive, somewhat inefficient, too heavy and in some instances unreliable.
In view of the above, the present aspirating horizontal mixer has been particularly directed to low cost manufacture, efficient operation, reliablility in use and is light weight for one or two man handling. The present mixer is of a design permitting total oxygen dispersion throughout an entire basin at low power levels generally not attainable in the past by the use of prior art devices. Moreover, the present mixer can be used in conjunction with existing surface and subsurface aeration and mixing devices.